gas alarm detector: 1.high sensitivity and high accrancy 2.detection of many ... -21 Portable Single Gas Detector1.PGas-21 Series Single Gas Detector has high sensitivity and high accrancy,2.it is suitable ... )RangeRefer to lectotype table for detailsAlarm indication90dB variable sound vibration alarm, overrange, alarm against insufficient quantity of electricityResponse time(CO, H2S, SO2 ...